Supermassive Black Hole is 30 Times Too Big for Its Galaxy

Researchers have uncovered a supermassive black hole that's startlingly large. Found in a recently discovered galaxy, the black hole is 30 times the size that researchers expected it to be.

The galaxy, named SAGE0536AGN, was initially found with NASA's Spitzer Space Telescope in infrared light. Thought to be at least 9 billion years old, the galaxy contains an active galactic nucleus, which is an incredibly bright object resulting from the accretion of gas by a central supermassive black hole. The gas is accelerated to high velocities due to the black hole's immense gravitational field, causing this cause to emit light.

The researchers have no confirmed the presence of the black hole by measuring the speed of the gas moving around it. Using the Southern African Large Telescope, the scientists observed that an emission line of hydrogen in the galaxy spectrum is broadened through the Doppler Effect, where the wavelength of light from objects is blue- or red-shifted depending on whether they are moving toward or away from us. The degree of broadening reveals that the gas is moving around at a high speed as a result of the black hole.

Using this data, the researchers also calculated the black hole's mass. They found that the black hole is 350 million times the mass of the sun. However, the galaxy itself is only about 25 billion solar masses. This means that the black hole is about thirty times larger than expected for the size of the galaxy.

"Galaxies have a vast mass, and so do the black holes at their cores," said Jacco van Loon, lead author of the new paper, in a news release. "This one though is really too big for its boots-it simply shouldn't be possible for it to be so large."